The White House warned Friday that President Obama might not sign a spending bill to keep the government running beyond next week unless Congress changes current law and requires corporations to disclose campaign donations.

White House press secretary Josh Earnest said Mr. Obama is concerned the spending bill renews language that “would essentially protect the ability of special interests to funnel money into political campaigns without having to disclose it.”

“I don’t really know what a proposal like that is doing in a budget bill,” he said. “It sounds to me like Republicans in Congress have more work to do to make sure the government doesn’t shut down a week from now.”

The measure on corporation campaign spending is already law; it was included in the spending bill for the current fiscal year that was approved by the president. Mr. Obama and Senate Democratic Leader Harry Reid of Nevada are pushing to strip it from the new spending bill.

Mr. Earnest said he spoke to Mr. Obama early Friday afternoon, and “it’s not at all clear to me that he is prepared to sign this bill.” He didn’t mention the word “veto” in describing the president’s objections.

Congress must pass a resolution by next Friday to keep the government open and avert a shutdown just weeks ahead of Election Day. The overall spending bill includes a so-called “rider” preventing the Securities and Exchange Commission from more tightly regulating corporate political spending.

The White House also said Mr. Obama is “concerned” that the spending bill does not address the water-contamination crisis in Flint, Michigan.